The effect of blood pressure variability on renal functional reserve at essential arterial hypertension І stage

Abstract

The article presents the results of the investigation impact of variability in blood pressure (BP) on renal functional reserve (RFR) in patients with essential hyper tension (EH) I stage.The objective: to determine the effect of the blood pressure variability on kidney function at EH І stage.Patients and methods. The study involved 50 patients. The study group included 30 patients with diagnosed essential hypertension I satge diagnosed according to the WHO/ISH, 2003 (World Health Organization/International Society of Hypertension) and Order of the Minister of Health of Ukraine (May, 24, 2012 No.384) (mean duration of EH 3,5±0,5 years, women – 12 (40%), men – 18 (60%), average age – 44,6±1,78 years); 20 healthy individ uals as the control group (women – 11 (55%), men – 9 (45%), average age – 41,1±1,96 years). Non – inclusion criteria were: symptomatic hypertension, valvular heart disease, arrhythmias, congestive heart failure, chronic kidney disease, diabetes, coronary heart disease. Patients of the main group were not taking antihypertensive therapy. All patients underwent following tests: clinical examination, general clinical blood and urine tests, urine albumin/creatinine ratio, biochemical blood tests (total protein, urea, creatinine, glucose, lipid profile); ambulatory blood pressure monitoring (ABPM) , ECG, EchO KG and ultrasound of the carotid arteries ), ophthalmoscopy; renal function reserve (RFR) was determined by water and salt load method (under patent Ukraine 42,860). ABPM performed on the monitor ABPM 50 (UK, 2015). The results were analyzed by the soft ware ABPM50.Results. Рatients of the main group had shown increased BP variability compared to the results of control group: SBP and DBP were significantly higher in EAG patheints (in 74,34% (p<0,001) and 76,74% (p<0,001), respectivel. Analyze of the night BP level has demonstrated that most of patients in main group had abnormal BP reaction: 12 (40%) persons were «non dipper», 3 (10%) – «night peaker», 9 (30%) – «over dipper»; normal circadian rhythm («dipper») was found in only 6 persons (20%). All persons from control group demonstrated «dipper» profile of the night BP. The mean RFR was signifi cantly lower in the main group (14,16±3,86%) than in the control group (34,04±10,63%; p<0,05). The lowest rate of RFR in study patients was determined in «night picker» and «non dipper» subgroups; and in patients with maximum degree of BP variability.Conclusions. 1. In hypertensive patients RFR is significantly reduced compared with healthy persons (14,16±3,86%) and (34,04±10,63%; p<0,001).2. Adverse nocturnal blood pressure profile («non dipper», «night peaker») observed in 50% of patients with EH I stage.3. The maximum reduction in RFR develops in «non dipper» (9,42±3,87%) and «night peaker» (5,56 ± 3,24%) subgroups .4. Maximal variability in SBP and DBP in EH I stage patients leads to decreased RFR/